phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'c81a8d3dfabd1927f407f0676e51a4c1' for key 1

INSERT INTO whatever_10_phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('c81a8d3dfabd1927f407f0676e51a4c1', -1, 1268442956, 1268442956, '0ab0a7b9', 2, 0, 0)

Line : 187
File : sessions.php